Solar radiation will dictate hazard today.
We've had 4 consecutive days with above freezing temperatures at our 2100m weather station. Don't let frozen valley bottom conditions lead you into a false sense of security!
Summary
Weather Forecast
A cold front sliding down the Rockies will spill some cloud cover over Rogers Pass today.
Today: mix of sun and cloud. Freezing levels rise to 1900m then begin to fall by midday (currently an alpine inversion still holds). Wind NE-25 km/h
Tonight: clear periods. Fzls drop to valley bottom. Wind NE 20-30km/h
Monday: mainly sunny. Fzl 1700m. Wind NE-10
Snowpack Summary
Temperatures above freezing for 4 nights at treeline and above. N aspects are still holding dry snow in the alpine. The April 7th layer is down 20-40cm depending on aspect and elevation, and the March 18th crust is down 60cm-1m. The mid and lower snowpack is very strong with old crusts and facets decomposing at the base.
Avalanche Summary
Explosives control yesterday afternoon yielded good results with numerous large wet slab and loose wet avalanches from steep SE through W aspects. Thursday and Friday afternoon saw a large natural avalanche cycle to sz 3.5 from solar start zones at all elevations, running into all aspects.
Confidence
Problems
Wet Slabs
Inverted temperatures and strong solar radiation today will elevate the hazard in solar exposed terrain including shaded aspects exposed to solar aspects from above. Crusts may break down early. Check out this link for more info on spring conditions.
- Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.
- Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.
Aspects: East, South East, South, South West, West.
Elevations: All elevations.
Likelihood
Expected Size
Cornices
Cornices continue to fail this week both naturally and human triggered. The sun is beating down on the top of cornices even over polar aspects. Avoid exposure to cornices
- Avoid travel on slopes that are exposed to cornices overhead.
- Give cornices a wide berth when travelling on or below ridges.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 19th, 2021 8:00AM
